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<h2><span class="refentrytitle"><a name="glib-Miscellaneous-Macros.top_of_page"></a>Miscellaneous Macros</span></h2>
<p>Miscellaneous Macros — specialized macros which are not used often</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<a name="glib-Miscellaneous-Macros.synopsis"></a><h2>Synopsis</h2>
<pre class="synopsis">
#include &lt;glib.h&gt;

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-INLINE-FUNC:CAPS" title="G_INLINE_FUNC">G_INLINE_FUNC</a>

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STMT-START:CAPS" title="G_STMT_START">G_STMT_START</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STMT-END:CAPS" title="G_STMT_END">G_STMT_END</a>

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-BEGIN-DECLS:CAPS" title="G_BEGIN_DECLS">G_BEGIN_DECLS</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-END-DECLS:CAPS" title="G_END_DECLS">G_END_DECLS</a>

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-N-ELEMENTS:CAPS" title="G_N_ELEMENTS()">G_N_ELEMENTS</a>                        (arr)

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-VA-COPY:CAPS" title="G_VA_COPY()">G_VA_COPY</a>                           (ap1,
                                                         ap2)

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STRINGIFY:CAPS" title="G_STRINGIFY()">G_STRINGIFY</a>                         (macro_or_string)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-PASTE:CAPS" title="G_PASTE()">G_PASTE</a>                             (identifier1,
                                                         identifier2)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STATIC-ASSERT:CAPS" title="G_STATIC_ASSERT()">G_STATIC_ASSERT</a>                     (expr)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STATIC-ASSERT-EXPR:CAPS" title="G_STATIC_ASSERT_EXPR()">G_STATIC_ASSERT_EXPR</a>                (expr)

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-EXTENSION:CAPS" title="G_GNUC_EXTENSION">G_GNUC_EXTENSION</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-CONST:CAPS" title="G_GNUC_CONST">G_GNUC_CONST</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-PURE:CAPS" title="G_GNUC_PURE">G_GNUC_PURE</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-MALLOC:CAPS" title="G_GNUC_MALLOC">G_GNUC_MALLOC</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-ALLOC-SIZE:CAPS" title="G_GNUC_ALLOC_SIZE()">G_GNUC_ALLOC_SIZE</a>                   (x)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-ALLOC-SIZE2:CAPS" title="G_GNUC_ALLOC_SIZE2()">G_GNUC_ALLOC_SIZE2</a>                  (x,
                                                         y)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-DEPRECATED:CAPS" title="G_GNUC_DEPRECATED">G_GNUC_DEPRECATED</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-DEPRECATED-FOR:CAPS" title="G_GNUC_DEPRECATED_FOR()">G_GNUC_DEPRECATED_FOR</a>               (f)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-NORETURN:CAPS" title="G_GNUC_NORETURN">G_GNUC_NORETURN</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-UNUSED:CAPS" title="G_GNUC_UNUSED">G_GNUC_UNUSED</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-PRINTF:CAPS" title="G_GNUC_PRINTF()">G_GNUC_PRINTF</a>                       (format_idx,
                                                         arg_idx)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-SCANF:CAPS" title="G_GNUC_SCANF()">G_GNUC_SCANF</a>                        (format_idx,
                                                         arg_idx)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-FORMAT:CAPS" title="G_GNUC_FORMAT()">G_GNUC_FORMAT</a>                       (arg_idx)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-NULL-TERMINATED:CAPS" title="G_GNUC_NULL_TERMINATED">G_GNUC_NULL_TERMINATED</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-WARN-UNUSED-RESULT:CAPS" title="G_GNUC_WARN_UNUSED_RESULT">G_GNUC_WARN_UNUSED_RESULT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-FUNCTION:CAPS" title="G_GNUC_FUNCTION">G_GNUC_FUNCTION</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-PRETTY-FUNCTION:CAPS" title="G_GNUC_PRETTY_FUNCTION">G_GNUC_PRETTY_FUNCTION</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-NO-INSTRUMENT:CAPS" title="G_GNUC_NO_INSTRUMENT">G_GNUC_NO_INSTRUMENT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-HAVE-GNUC-VISIBILITY:CAPS" title="G_HAVE_GNUC_VISIBILITY">G_HAVE_GNUC_VISIBILITY</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-INTERNAL:CAPS" title="G_GNUC_INTERNAL">G_GNUC_INTERNAL</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-MAY-ALIAS:CAPS" title="G_GNUC_MAY_ALIAS">G_GNUC_MAY_ALIAS</a>

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-LIKELY:CAPS" title="G_LIKELY()">G_LIKELY</a>                            (expr)
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-UNLIKELY:CAPS" title="G_UNLIKELY()">G_UNLIKELY</a>                          (expr)

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STRLOC:CAPS" title="G_STRLOC">G_STRLOC</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-STRFUNC:CAPS" title="G_STRFUNC">G_STRFUNC</a>

#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-MODIFIER:CAPS" title="G_GINT16_MODIFIER">G_GINT16_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT">G_GINT16_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GUINT16-FORMAT:CAPS" title="G_GUINT16_FORMAT">G_GUINT16_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT32-MODIFIER:CAPS" title="G_GINT32_MODIFIER">G_GINT32_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT32-FORMAT:CAPS" title="G_GINT32_FORMAT">G_GINT32_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GUINT32-FORMAT:CAPS" title="G_GUINT32_FORMAT">G_GUINT32_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-MODIFIER:CAPS" title="G_GINT64_MODIFIER">G_GINT64_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-FORMAT:CAPS" title="G_GINT64_FORMAT">G_GINT64_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GUINT64-FORMAT:CAPS" title="G_GUINT64_FORMAT">G_GUINT64_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GSIZE-MODIFIER:CAPS" title="G_GSIZE_MODIFIER">G_GSIZE_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GSIZE-FORMAT:CAPS" title="G_GSIZE_FORMAT">G_GSIZE_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GSSIZE-FORMAT:CAPS" title="G_GSSIZE_FORMAT">G_GSSIZE_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GOFFSET-MODIFIER:CAPS" title="G_GOFFSET_MODIFIER">G_GOFFSET_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GOFFSET-FORMAT:CAPS" title="G_GOFFSET_FORMAT">G_GOFFSET_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINTPTR-MODIFIER:CAPS" title="G_GINTPTR_MODIFIER">G_GINTPTR_MODIFIER</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GINTPTR-FORMAT:CAPS" title="G_GINTPTR_FORMAT">G_GINTPTR_FORMAT</a>
#define             <a class="link" href="glib-Miscellaneous-Macros.html#G-GUINTPTR-FORMAT:CAPS" title="G_GUINTPTR_FORMAT">G_GUINTPTR_FORMAT</a>
</pre>
</div>
<div class="refsect1">
<a name="glib-Miscellaneous-Macros.description"></a><h2>Description</h2>
<p>
These macros provide more specialized features which are not needed so often
by application programmers.
</p>
</div>
<div class="refsect1">
<a name="glib-Miscellaneous-Macros.details"></a><h2>Details</h2>
<div class="refsect2">
<a name="G-INLINE-FUNC:CAPS"></a><h3>G_INLINE_FUNC</h3>
<pre class="programlisting">#  define G_INLINE_FUNC
</pre>
<p>
This macro is used to export function prototypes so they can be linked
with an external version when no inlining is performed. The file which
implements the functions should define <code class="literal">G_IMPLEMENTS_INLINES</code>
before including the headers which contain <a class="link" href="glib-Miscellaneous-Macros.html#G-INLINE-FUNC:CAPS" title="G_INLINE_FUNC"><code class="literal">G_INLINE_FUNC</code></a> declarations.
Since inlining is very compiler-dependent using these macros correctly
is very difficult. Their use is strongly discouraged.
</p>
<p>
This macro is often mistaken for a replacement for the inline keyword;
inline is already declared in a portable manner in the glib headers
and can be used normally.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STMT-START:CAPS"></a><h3>G_STMT_START</h3>
<pre class="programlisting">#  define G_STMT_START  do
</pre>
<p>
Used within multi-statement macros so that they can be used in places where
only one statement is expected by the compiler.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STMT-END:CAPS"></a><h3>G_STMT_END</h3>
<pre class="programlisting">#  define G_STMT_END    while (0)
</pre>
<p>
Used within multi-statement macros so that they can be used in places where
only one statement is expected by the compiler.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-BEGIN-DECLS:CAPS"></a><h3>G_BEGIN_DECLS</h3>
<pre class="programlisting"># define G_BEGIN_DECLS  extern "C" {
</pre>
<p>
Used (along with <a class="link" href="glib-Miscellaneous-Macros.html#G-END-DECLS:CAPS" title="G_END_DECLS"><span class="type">G_END_DECLS</span></a>) to bracket header files. If the
compiler in use is a C++ compiler, adds <code class="literal">extern "C"</code>
around the header.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-END-DECLS:CAPS"></a><h3>G_END_DECLS</h3>
<pre class="programlisting"># define G_END_DECLS    }
</pre>
<p>
Used (along with <a class="link" href="glib-Miscellaneous-Macros.html#G-BEGIN-DECLS:CAPS" title="G_BEGIN_DECLS"><span class="type">G_BEGIN_DECLS</span></a>) to bracket header files. If the
compiler in use is a C++ compiler, adds <code class="literal">extern "C"</code>
around the header.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-N-ELEMENTS:CAPS"></a><h3>G_N_ELEMENTS()</h3>
<pre class="programlisting">#define G_N_ELEMENTS(arr)		(sizeof (arr) / sizeof ((arr)[0]))
</pre>
<p>
Determines the number of elements in an array. The array must be
declared so the compiler knows its size at compile-time; this
macro will not work on an array allocated on the heap, only static
arrays or arrays on the stack.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>arr</code></em> :</span></p></td>
<td>the array</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-VA-COPY:CAPS"></a><h3>G_VA_COPY()</h3>
<pre class="programlisting">#define             G_VA_COPY(ap1,ap2)</pre>
<p>
Portable way to copy <span class="type">va_list</span> variables.
</p>
<p>
In order to use this function, you must include <code class="filename">string.h</code>
yourself, because this macro may use <code class="function"><code class="function">memmove()</code></code> and GLib
does not include <code class="function">string.h</code> for you.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>ap1</code></em> :</span></p></td>
<td>the <span class="type">va_list</span> variable to place a copy of <em class="parameter"><code>ap2</code></em> in.</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>ap2</code></em> :</span></p></td>
<td>a <span class="type">va_list</span>.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-STRINGIFY:CAPS"></a><h3>G_STRINGIFY()</h3>
<pre class="programlisting">#define G_STRINGIFY(macro_or_string) G_STRINGIFY_ARG (macro_or_string)
</pre>
<p>
Accepts a macro or a string and converts it into a string after
preprocessor argument expansion. For example, the following code:
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="preproc">#define</span><span class="normal"> AGE </span><span class="number">27</span>
<span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">greeting </span><span class="symbol">=</span><span class="normal"> </span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-STRINGIFY:CAPS">G_STRINGIFY</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">AGE</span><span class="symbol">)</span><span class="normal"> </span><span class="string">" today!"</span><span class="symbol">;</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p>
is transformed by the preprocessor into (code equivalent to):
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">greeting </span><span class="symbol">=</span><span class="normal"> </span><span class="string">"27 today!"</span><span class="symbol">;</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>macro_or_string</code></em> :</span></p></td>
<td>a macro or a string.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-PASTE:CAPS"></a><h3>G_PASTE()</h3>
<pre class="programlisting">#define G_PASTE(identifier1,identifier2)      G_PASTE_ARGS (identifier1, identifier2)
</pre>
<p>
Yields a new preprocessor pasted identifier <code class="code">identifier1identifier2</code>
from its expanded arguments <em class="parameter"><code>identifier1</code></em> and <em class="parameter"><code>identifier2</code></em>. For example, the
following code:
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
4</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="preproc">#define</span><span class="normal"> </span><span class="function">GET</span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">,</span><span class="normal">method</span><span class="symbol">)</span><span class="normal"> </span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-PASTE:CAPS">G_PASTE</a></span><span class="symbol">(</span><span class="normal">traveller_get_</span><span class="symbol">,</span><span class="normal"> method</span><span class="symbol">)</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">)</span>
<span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">name </span><span class="symbol">=</span><span class="normal"> </span><span class="function">GET</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">,</span><span class="normal"> name</span><span class="symbol">);</span>
<span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">quest </span><span class="symbol">=</span><span class="normal"> </span><span class="function">GET</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">,</span><span class="normal"> quest</span><span class="symbol">);</span>
<span class="usertype">GdkColor</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">favourite </span><span class="symbol">=</span><span class="normal"> </span><span class="function">GET</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">,</span><span class="normal"> favourite_colour</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p>
is transformed by the preprocessor into:
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">name </span><span class="symbol">=</span><span class="normal"> </span><span class="function">traveller_get_name</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">);</span>
<span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">quest </span><span class="symbol">=</span><span class="normal"> </span><span class="function">traveller_get_quest</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">);</span>
<span class="usertype">GdkColor</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">favourite </span><span class="symbol">=</span><span class="normal"> </span><span class="function">traveller_get_favourite_colour</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">traveller</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>identifier1</code></em> :</span></p></td>
<td>an identifier</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>identifier2</code></em> :</span></p></td>
<td>an identifier</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 2.20</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STATIC-ASSERT:CAPS"></a><h3>G_STATIC_ASSERT()</h3>
<pre class="programlisting">#define G_STATIC_ASSERT(expr) typedef struct { char Compile_Time_Assertion[(expr) ? 1 : -1]; } G_PASTE (_GStaticAssert_, __LINE__)
</pre>
<p>
The G_STATIC_ASSERT macro lets the programmer check a condition at compile time,
the condition needs to be compile time computable.
The macro can be used in any place where a <code class="literal">typedef</code> is valid.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
A <code class="literal">typedef</code> is generally allowed in exactly the same
places that a variable declaration is allowed.  For this reason, you should not use <code class="literal">G_STATIC_ASSERT</code> in the middle of blocks of code.
</p>
</div>
<p>
The macro should only be used once per source code line.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>expr</code></em> :</span></p></td>
<td>a constant expression.</td>
</tr></tbody>
</table></div>
<p class="since">Since 2.20</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STATIC-ASSERT-EXPR:CAPS"></a><h3>G_STATIC_ASSERT_EXPR()</h3>
<pre class="programlisting">#define G_STATIC_ASSERT_EXPR(expr) ((void) sizeof (char[(expr) ? 1 : -1]))
</pre>
<p>
The G_STATIC_ASSERT_EXPR macro lets the programmer check a condition at
compile time.  The condition needs to be compile time computable.
</p>
<p>
Unlike <code class="literal">G_STATIC_ASSERT</code>, this macro evaluates to an
expression and, as such, can be used in the middle of other expressions.
Its value should be ignored.  This can be accomplished by placing it as
the first argument of a comma expression.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="preproc">#define</span><span class="normal"> </span><span class="function">ADD_ONE_TO_INT</span><span class="symbol">(</span><span class="normal">x</span><span class="symbol">)</span><span class="normal"> </span><span class="symbol">\</span>
<span class="normal">  </span><span class="symbol">(</span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-STATIC-ASSERT-EXPR:CAPS">G_STATIC_ASSERT_EXPR</a></span><span class="symbol">(</span><span class="keyword">sizeof</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">x</span><span class="symbol">)</span><span class="normal"> </span><span class="symbol">==</span><span class="normal"> </span><span class="keyword">sizeof</span><span class="normal"> </span><span class="symbol">(</span><span class="type">int</span><span class="symbol">)),</span><span class="normal"> </span><span class="symbol">((</span><span class="normal">x</span><span class="symbol">)</span><span class="normal"> </span><span class="symbol">+</span><span class="normal"> </span><span class="number">1</span><span class="symbol">))</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>expr</code></em> :</span></p></td>
<td>a constant expression.</td>
</tr></tbody>
</table></div>
<p class="since">Since 2.30</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-EXTENSION:CAPS"></a><h3>G_GNUC_EXTENSION</h3>
<pre class="programlisting">#  define G_GNUC_EXTENSION __extension__
</pre>
<p>
Expands to <code class="literal">__extension__</code> when <span class="command"><strong>gcc</strong></span> is
used as the compiler.
This simply tells <span class="command"><strong>gcc</strong></span> not to warn about the following non-standard code
when compiling with the <code class="option">-pedantic</code> option.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-CONST:CAPS"></a><h3>G_GNUC_CONST</h3>
<pre class="programlisting">#define             G_GNUC_CONST</pre>
<p>
Expands to the GNU C <code class="literal">const</code> function attribute if the compiler is
<span class="command"><strong>gcc</strong></span>. Declaring a function as const enables better optimization of calls
to the function. A const function doesn't examine any values except its parameters, and has no
effects except its return value. See the GNU C documentation for details.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
A function that has pointer arguments and examines the data pointed to
must <span class="emphasis"><em>not</em></span> be declared const. Likewise, a function that
calls a non-const function usually must not be const. It doesn't make sense
for a const function to return void.
</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-PURE:CAPS"></a><h3>G_GNUC_PURE</h3>
<pre class="programlisting">#define             G_GNUC_PURE</pre>
<p>
Expands to the GNU C <code class="literal">pure</code> function attribute if the compiler is
<span class="command"><strong>gcc</strong></span>. Declaring a function as pure enables better optimization of
calls to the function. A pure function has no effects except its return value and the
return value depends only on the parameters and/or global variables.
See the GNU C documentation for details.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-MALLOC:CAPS"></a><h3>G_GNUC_MALLOC</h3>
<pre class="programlisting">#define             G_GNUC_MALLOC</pre>
<p>
Expands to the GNU C <code class="literal">malloc</code> function attribute if the
compiler is <span class="command"><strong>gcc</strong></span>. Declaring a function as malloc enables
better optimization of the function. A function can have the malloc attribute
if it returns a pointer which is guaranteed to not alias with any other pointer
when the function returns (in practice, this means newly allocated memory).
See the GNU C documentation for details.
</p>
<p class="since">Since 2.6</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-ALLOC-SIZE:CAPS"></a><h3>G_GNUC_ALLOC_SIZE()</h3>
<pre class="programlisting">#define G_GNUC_ALLOC_SIZE(x) __attribute__((__alloc_size__(x)))
</pre>
<p>
Expands to the GNU C <code class="literal">alloc_size</code> function attribute if the
compiler is a new enough <span class="command"><strong>gcc</strong></span>. This attribute tells the
compiler that the function returns a pointer to memory of a size that is
specified by the <em class="parameter"><code>x</code></em>th function parameter.
See the GNU C documentation for details.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>the index of the argument specifying the allocation size</td>
</tr></tbody>
</table></div>
<p class="since">Since 2.18</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-ALLOC-SIZE2:CAPS"></a><h3>G_GNUC_ALLOC_SIZE2()</h3>
<pre class="programlisting">#define G_GNUC_ALLOC_SIZE2(x,y) __attribute__((__alloc_size__(x,y)))
</pre>
<p>
Expands to the GNU C <code class="literal">alloc_size</code> function attribute if the
compiler is a new enough <span class="command"><strong>gcc</strong></span>. This attribute tells the
compiler that the function returns a pointer to memory of a size that is
specified by the product of two function parameters.
See the GNU C documentation for details.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>x</code></em> :</span></p></td>
<td>the index of the argument specifying one factor of the allocation size</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>y</code></em> :</span></p></td>
<td>the index of the argument specifying the second factor of the allocation size</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 2.18</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-DEPRECATED:CAPS"></a><h3>G_GNUC_DEPRECATED</h3>
<pre class="programlisting">#define             G_GNUC_DEPRECATED</pre>
<p>
Expands to the GNU C <code class="literal">deprecated</code> attribute if the compiler
is <span class="command"><strong>gcc</strong></span>.
It can be used to mark typedefs, variables and functions as deprecated.
When called with the <code class="option">-Wdeprecated-declarations</code> option, the compiler will
generate warnings when deprecated interfaces are used.
See the GNU C documentation for details.
</p>
<p class="since">Since 2.2</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-DEPRECATED-FOR:CAPS"></a><h3>G_GNUC_DEPRECATED_FOR()</h3>
<pre class="programlisting">#define             G_GNUC_DEPRECATED_FOR(f)</pre>
<p>
Like <a class="link" href="glib-Miscellaneous-Macros.html#G-GNUC-DEPRECATED:CAPS" title="G_GNUC_DEPRECATED"><code class="literal">G_GNUC_DEPRECATED</code></a>, but names the intended replacement for the
deprecated symbol if the version of <span class="command"><strong>gcc</strong></span> in use is
new enough to support custom deprecation messages.
See the GNU C documentation for details.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>f</code></em> :</span></p></td>
<td>the intended replacement for the deprecated symbol, such as the name of a
function</td>
</tr></tbody>
</table></div>
<p class="since">Since 2.26</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-NORETURN:CAPS"></a><h3>G_GNUC_NORETURN</h3>
<pre class="programlisting">#define             G_GNUC_NORETURN</pre>
<p>
Expands to the GNU C <code class="literal">noreturn</code> function attribute if the
compiler is <span class="command"><strong>gcc</strong></span>. It is used for declaring functions which never return.
It enables optimization of the function, and avoids possible compiler
warnings. See the GNU C documentation for details.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-UNUSED:CAPS"></a><h3>G_GNUC_UNUSED</h3>
<pre class="programlisting">#define             G_GNUC_UNUSED</pre>
<p>
Expands to the GNU C <code class="literal">unused</code> function attribute if the compiler is
<span class="command"><strong>gcc</strong></span>. It is used for declaring functions which may never be used.
It avoids possible compiler warnings. See the GNU C documentation for details.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-PRINTF:CAPS"></a><h3>G_GNUC_PRINTF()</h3>
<pre class="programlisting">#define             G_GNUC_PRINTF( format_idx, arg_idx )</pre>
<p>
Expands to the GNU C <code class="literal">format</code> function attribute if the compiler is
<span class="command"><strong>gcc</strong></span>. This is used for declaring functions which take a variable number of
arguments, with the same syntax as <code class="function"><code class="function">printf()</code></code>.
It allows the compiler to type-check the arguments passed to the function.
See the GNU C documentation for details.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
4</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="usertype">gint</span><span class="normal"> </span><span class="function"><a href="glib-String-Utility-Functions.html#g-snprintf">g_snprintf</a></span><span class="normal"> </span><span class="symbol">(</span><span class="usertype">gchar</span><span class="normal">  </span><span class="symbol">*</span><span class="normal">string</span><span class="symbol">,</span>
<span class="normal">                 </span><span class="usertype">gulong</span><span class="normal">       n</span><span class="symbol">,</span>
<span class="normal">                 </span><span class="usertype">gchar</span><span class="normal"> </span><span class="keyword">const</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">format</span><span class="symbol">,</span>
<span class="normal">                 </span><span class="symbol">...)</span><span class="normal"> </span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-GNUC-PRINTF:CAPS">G_GNUC_PRINTF</a></span><span class="normal"> </span><span class="symbol">(</span><span class="number">3</span><span class="symbol">,</span><span class="normal"> </span><span class="number">4</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>format_idx</code></em> :</span></p></td>
<td>the index of the argument corresponding to the format string.
(The arguments are numbered from 1).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>arg_idx</code></em> :</span></p></td>
<td>the index of the first of the format arguments.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-SCANF:CAPS"></a><h3>G_GNUC_SCANF()</h3>
<pre class="programlisting">#define             G_GNUC_SCANF( format_idx, arg_idx )</pre>
<p>
Expands to the GNU C <code class="literal">format</code> function attribute if the compiler is <span class="command"><strong>gcc</strong></span>.
This is used for declaring functions which take a variable number of
arguments, with the same syntax as <code class="function"><code class="function">scanf()</code></code>.
It allows the compiler to type-check the arguments passed to the function.
See the GNU C documentation for details.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>format_idx</code></em> :</span></p></td>
<td>the index of the argument corresponding to the format string.
(The arguments are numbered from 1).</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>arg_idx</code></em> :</span></p></td>
<td>the index of the first of the format arguments.</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-FORMAT:CAPS"></a><h3>G_GNUC_FORMAT()</h3>
<pre class="programlisting">#define             G_GNUC_FORMAT( arg_idx )</pre>
<p>
Expands to the GNU C <code class="literal">format_arg</code> function attribute if the compiler is <span class="command"><strong>gcc</strong></span>.
This function attribute specifies that a function takes a format
string for a <code class="function"><code class="function">printf()</code></code>, <code class="function"><code class="function">scanf()</code></code>,
<code class="function"><code class="function">strftime()</code></code> or <code class="function"><code class="function">strfmon()</code></code> style
function and modifies it, so that the result can be passed to a
<code class="function"><code class="function">printf()</code></code>, <code class="function"><code class="function">scanf()</code></code>,
<code class="function"><code class="function">strftime()</code></code> or <code class="function"><code class="function">strfmon()</code></code> style
function (with the remaining arguments to the format function the same as
they would have been for the unmodified string).
See the GNU C documentation for details.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="function"><a href="glib-I18N.html#g-dgettext">g_dgettext</a></span><span class="normal"> </span><span class="symbol">(</span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">domain_name</span><span class="symbol">,</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">msgid</span><span class="symbol">)</span><span class="normal"> </span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-GNUC-FORMAT:CAPS">G_GNUC_FORMAT</a></span><span class="normal"> </span><span class="symbol">(</span><span class="number">2</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><p><span class="term"><em class="parameter"><code>arg_idx</code></em> :</span></p></td>
<td>the index of the argument.</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-NULL-TERMINATED:CAPS"></a><h3>G_GNUC_NULL_TERMINATED</h3>
<pre class="programlisting">#define G_GNUC_NULL_TERMINATED __attribute__((__sentinel__))
</pre>
<p>
Expands to the GNU C <code class="literal">sentinel</code> function attribute if the
compiler is <span class="command"><strong>gcc</strong></span>, or "" if it isn't. This function attribute
only applies to variadic functions and instructs the compiler to check that
the argument list is terminated with an explicit <a class="link" href="glib-Standard-Macros.html#NULL:CAPS" title="NULL"><code class="literal">NULL</code></a>.
See the GNU C documentation for details.
</p>
Since: 2.8</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-WARN-UNUSED-RESULT:CAPS"></a><h3>G_GNUC_WARN_UNUSED_RESULT</h3>
<pre class="programlisting">#define             G_GNUC_WARN_UNUSED_RESULT</pre>
<p>
Expands to the GNU C <code class="literal">warn_unused_result</code> function attribute
if the compiler is <span class="command"><strong>gcc</strong></span>, or "" if it isn't. This function
attribute makes the compiler emit a warning if the result of a function call
is ignored. See the GNU C documentation for details.
</p>
<p class="since">Since 2.10</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-FUNCTION:CAPS"></a><h3>G_GNUC_FUNCTION</h3>
<pre class="programlisting">#define G_GNUC_FUNCTION         __FUNCTION__
</pre>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Warning</h3>
<p><code class="literal">G_GNUC_FUNCTION</code> has been deprecated since version 2.16 and should not be used in newly-written code. Use <a class="link" href="glib-Miscellaneous-Macros.html#G-STRFUNC:CAPS" title="G_STRFUNC"><span class="type">G_STRFUNC</span></a> instead.</p>
</div>
<p>
Expands to "" on all modern compilers, and to <code class="literal">__FUNCTION__</code>
on <span class="command"><strong>gcc</strong></span> version 2.x. Don't use it.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-PRETTY-FUNCTION:CAPS"></a><h3>G_GNUC_PRETTY_FUNCTION</h3>
<pre class="programlisting">#define G_GNUC_PRETTY_FUNCTION  __PRETTY_FUNCTION__
</pre>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Warning</h3>
<p><code class="literal">G_GNUC_PRETTY_FUNCTION</code> has been deprecated since version 2.16 and should not be used in newly-written code. Use <a class="link" href="glib-Miscellaneous-Macros.html#G-STRFUNC:CAPS" title="G_STRFUNC"><span class="type">G_STRFUNC</span></a> instead.</p>
</div>
<p>
Expands to "" on all modern compilers, and to
<code class="literal">__PRETTY_FUNCTION__</code> on <span class="command"><strong>gcc</strong></span> version 2.x.
Don't use it.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-NO-INSTRUMENT:CAPS"></a><h3>G_GNUC_NO_INSTRUMENT</h3>
<pre class="programlisting">#define             G_GNUC_NO_INSTRUMENT</pre>
<p>
Expands to the GNU C <code class="literal">no_instrument_function</code> function
attribute if the compiler is <span class="command"><strong>gcc</strong></span>. Functions with this
attribute will not be
instrumented for profiling, when the compiler is called with the
<code class="option">-finstrument-functions</code> option.
See the GNU C documentation for details.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-HAVE-GNUC-VISIBILITY:CAPS"></a><h3>G_HAVE_GNUC_VISIBILITY</h3>
<pre class="programlisting">#define G_HAVE_GNUC_VISIBILITY 1
</pre>
<p>
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-INTERNAL:CAPS"></a><h3>G_GNUC_INTERNAL</h3>
<pre class="programlisting">#define G_GNUC_INTERNAL __attribute__((visibility("hidden")))
</pre>
<p>
This attribute can be used for marking library functions as being used
internally to the library only, which may allow the compiler to handle
function calls more efficiently.
Note that static functions do not need to be marked as internal in this way.
See the GNU C documentation for details.
</p>
<p>
When using a compiler that supports the GNU C hidden visibility attribute,
this macro expands to <code class="literal">__attribute__((visibility("hidden")))</code>.
When using the Sun Studio compiler, it expands to <code class="literal">__hidden</code>.
</p>
<p>
Note that for portability, the attribute should be placed before the
function declaration. While GCC allows the macro after the declaration,
Sun Studio does not.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
4
5</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="normal"><a href="glib-Miscellaneous-Macros.html#G-GNUC-INTERNAL:CAPS">G_GNUC_INTERNAL</a></span>
<span class="type">void</span><span class="normal"> </span><span class="function">_g_log_fallback_handler</span><span class="normal"> </span><span class="symbol">(</span><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal">    </span><span class="symbol">*</span><span class="normal">log_domain</span><span class="symbol">,</span>
<span class="normal">                              </span><span class="usertype">GLogLevelFlags</span><span class="normal">  log_level</span><span class="symbol">,</span>
<span class="normal">                              </span><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal">    </span><span class="symbol">*</span><span class="normal">message</span><span class="symbol">,</span>
<span class="normal">                              </span><span class="usertype">gpointer</span><span class="normal">        unused_data</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

Since: 2.6</div>
<hr>
<div class="refsect2">
<a name="G-GNUC-MAY-ALIAS:CAPS"></a><h3>G_GNUC_MAY_ALIAS</h3>
<pre class="programlisting">#  define G_GNUC_MAY_ALIAS __attribute__((may_alias))
</pre>
<p>
Expands to the GNU C <code class="literal">may_alias</code> type attribute
if the compiler is <span class="command"><strong>gcc</strong></span>. Types with this attribute
will not be subjected to type-based alias analysis, but are assumed
to alias with any other type, just like char.
See the GNU C documentation for details.
</p>
Since: 2.14</div>
<hr>
<div class="refsect2">
<a name="G-LIKELY:CAPS"></a><h3>G_LIKELY()</h3>
<pre class="programlisting">#define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 1))
</pre>
<p>
Hints the compiler that the expression is likely to evaluate to a true
value. The compiler may use this information for optimizations.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-LIKELY:CAPS">G_LIKELY</a></span><span class="normal"> </span><span class="symbol">(</span><span class="function">random</span><span class="normal"> </span><span class="symbol">()</span><span class="normal"> </span><span class="symbol">!=</span><span class="normal"> </span><span class="number">1</span><span class="symbol">))</span>
<span class="normal">  </span><span class="function"><a href="glib-Warnings-and-Assertions.html#g-print">g_print</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"not one"</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>expr</code></em> :</span></p></td>
<td>the expression</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the value of <em class="parameter"><code>expr</code></em>
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 2.2</p>
</div>
<hr>
<div class="refsect2">
<a name="G-UNLIKELY:CAPS"></a><h3>G_UNLIKELY()</h3>
<pre class="programlisting">#define G_UNLIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR(expr), 0))
</pre>
<p>
Hints the compiler that the expression is unlikely to evaluate to a true
value. The compiler may use this information for optimizations.
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="function"><a href="glib-Miscellaneous-Macros.html#G-UNLIKELY:CAPS">G_UNLIKELY</a></span><span class="normal"> </span><span class="symbol">(</span><span class="function">random</span><span class="normal"> </span><span class="symbol">()</span><span class="normal"> </span><span class="symbol">==</span><span class="normal"> </span><span class="number">1</span><span class="symbol">))</span>
<span class="normal">  </span><span class="function"><a href="glib-Warnings-and-Assertions.html#g-print">g_print</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"a random one"</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>expr</code></em> :</span></p></td>
<td>the expression</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
<td>the value of <em class="parameter"><code>expr</code></em>
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since 2.2</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STRLOC:CAPS"></a><h3>G_STRLOC</h3>
<pre class="programlisting">#  define G_STRLOC __FILE__ ":" G_STRINGIFY (__LINE__) ":" __PRETTY_FUNCTION__ "()"
</pre>
<p>
Expands to a string identifying the current code position.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-STRFUNC:CAPS"></a><h3>G_STRFUNC</h3>
<pre class="programlisting">#  define G_STRFUNC     ((const char*) (__PRETTY_FUNCTION__))
</pre>
<p>
Expands to a string identifying the current function.
</p>
<p class="since">Since 2.4</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT16-MODIFIER:CAPS"></a><h3>G_GINT16_MODIFIER</h3>
<pre class="programlisting">#define G_GINT16_MODIFIER "h"
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#gint16" title="gint16"><span class="type">gint16</span></a> or <a class="link" href="glib-Basic-Types.html#guint16" title="guint16"><span class="type">guint16</span></a>. It is a string literal,
but doesn't include the percent-sign, such that you can add precision and
length modifiers between percent-sign and conversion specifier and append a
conversion specifier.
</p>
<p>
The following example prints "0x7b";
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="usertype">gint16</span><span class="normal"> value </span><span class="symbol">=</span><span class="normal"> </span><span class="number">123</span><span class="symbol">;</span>
<span class="function"><a href="glib-Warnings-and-Assertions.html#g-print">g_print</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"%#"</span><span class="normal"> <a href="glib-Miscellaneous-Macros.html#G-GINT16-MODIFIER:CAPS">G_GINT16_MODIFIER</a> </span><span class="string">"x"</span><span class="symbol">,</span><span class="normal"> value</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p>
</p>
<p class="since">Since 2.4</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT16-FORMAT:CAPS"></a><h3>G_GINT16_FORMAT</h3>
<pre class="programlisting">#define G_GINT16_FORMAT "hi"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gint16" title="gint16"><span class="type">gint16</span></a>. It is a string literal, but doesn't
include the percent-sign, such that you can add precision and length
modifiers between percent-sign and conversion specifier.
</p>
<p>
</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2
3
4
5</pre></td>
        <td class="listing_code"><pre class="programlisting"><span class="usertype">gint16</span><span class="normal"> in</span><span class="symbol">;</span>
<span class="usertype">gint32</span><span class="normal"> out</span><span class="symbol">;</span>
<span class="function">sscanf</span><span class="normal"> </span><span class="symbol">(</span><span class="string">"42"</span><span class="symbol">,</span><span class="normal"> </span><span class="string">"%"</span><span class="normal"> <a href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS">G_GINT16_FORMAT</a></span><span class="symbol">,</span><span class="normal"> </span><span class="symbol">&amp;</span><span class="normal">in</span><span class="symbol">)</span>
<span class="normal">out </span><span class="symbol">=</span><span class="normal"> in </span><span class="symbol">*</span><span class="normal"> </span><span class="number">1000</span><span class="symbol">;</span>
<span class="function"><a href="glib-Warnings-and-Assertions.html#g-print">g_print</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"%"</span><span class="normal"> <a href="glib-Miscellaneous-Macros.html#G-GINT32-FORMAT:CAPS">G_GINT32_FORMAT</a></span><span class="symbol">,</span><span class="normal"> out</span><span class="symbol">);</span></pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p>
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GUINT16-FORMAT:CAPS"></a><h3>G_GUINT16_FORMAT</h3>
<pre class="programlisting">#define G_GUINT16_FORMAT "hu"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#guint16" title="guint16"><span class="type">guint16</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT32-MODIFIER:CAPS"></a><h3>G_GINT32_MODIFIER</h3>
<pre class="programlisting">#define G_GINT32_MODIFIER ""
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#gint32" title="gint32"><span class="type">gint32</span></a> or <a class="link" href="glib-Basic-Types.html#guint32" title="guint32"><span class="type">guint32</span></a>. It is a string literal,
See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-MODIFIER:CAPS" title="G_GINT16_MODIFIER"><span class="type">G_GINT16_MODIFIER</span></a>.
</p>
<p class="since">Since 2.4</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT32-FORMAT:CAPS"></a><h3>G_GINT32_FORMAT</h3>
<pre class="programlisting">#define G_GINT32_FORMAT "i"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gint32" title="gint32"><span class="type">gint32</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GUINT32-FORMAT:CAPS"></a><h3>G_GUINT32_FORMAT</h3>
<pre class="programlisting">#define G_GUINT32_FORMAT "u"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#guint32" title="guint32"><span class="type">guint32</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT64-MODIFIER:CAPS"></a><h3>G_GINT64_MODIFIER</h3>
<pre class="programlisting">#define G_GINT64_MODIFIER "l"
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#gint64" title="gint64"><span class="type">gint64</span></a> or <a class="link" href="glib-Basic-Types.html#guint64" title="guint64"><span class="type">guint64</span></a>. It is a string literal.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
Some platforms do not support printing 64 bit integers,
even though the types are supported. On such platforms <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-MODIFIER:CAPS" title="G_GINT64_MODIFIER"><span class="type">G_GINT64_MODIFIER</span></a>
is not defined.
</p>
</div>
<p class="since">Since 2.4</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINT64-FORMAT:CAPS"></a><h3>G_GINT64_FORMAT</h3>
<pre class="programlisting">#define G_GINT64_FORMAT "li"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gint64" title="gint64"><span class="type">gint64</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
Some platforms do not support scanning and printing 64 bit integers,
even though the types are supported. On such platforms <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-FORMAT:CAPS" title="G_GINT64_FORMAT"><span class="type">G_GINT64_FORMAT</span></a>
is not defined. Note that <code class="function">scanf()</code> may not support 64 bit integers, even
if <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-FORMAT:CAPS" title="G_GINT64_FORMAT"><span class="type">G_GINT64_FORMAT</span></a> is defined. Due to its weak error handling, <code class="function">scanf()</code>
is not recommended for parsing anyway; consider using <a class="link" href="glib-String-Utility-Functions.html#g-ascii-strtoull" title="g_ascii_strtoull ()"><code class="function">g_ascii_strtoull()</code></a>
instead.
</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="G-GUINT64-FORMAT:CAPS"></a><h3>G_GUINT64_FORMAT</h3>
<pre class="programlisting">#define G_GUINT64_FORMAT "lu"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#guint64" title="guint64"><span class="type">guint64</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
Some platforms do not support scanning and printing 64 bit integers,
even though the types are supported. On such platforms <a class="link" href="glib-Miscellaneous-Macros.html#G-GUINT64-FORMAT:CAPS" title="G_GUINT64_FORMAT"><span class="type">G_GUINT64_FORMAT</span></a>
is not defined.  Note that <code class="function">scanf()</code> may not support 64 bit integers, even
if <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-FORMAT:CAPS" title="G_GINT64_FORMAT"><span class="type">G_GINT64_FORMAT</span></a> is defined. Due to its weak error handling, <code class="function">scanf()</code>
is not recommended for parsing anyway; consider using <a class="link" href="glib-String-Utility-Functions.html#g-ascii-strtoull" title="g_ascii_strtoull ()"><code class="function">g_ascii_strtoull()</code></a>
instead.
</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="G-GSIZE-MODIFIER:CAPS"></a><h3>G_GSIZE_MODIFIER</h3>
<pre class="programlisting">#define G_GSIZE_MODIFIER "l"
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a> or <a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a>. It is a string literal,
</p>
<p class="since">Since 2.6</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GSIZE-FORMAT:CAPS"></a><h3>G_GSIZE_FORMAT</h3>
<pre class="programlisting">#define G_GSIZE_FORMAT "lu"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gsize" title="gsize"><span class="type">gsize</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
<p class="since">Since 2.6</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GSSIZE-FORMAT:CAPS"></a><h3>G_GSSIZE_FORMAT</h3>
<pre class="programlisting">#define G_GSSIZE_FORMAT "li"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gssize" title="gssize"><span class="type">gssize</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT16-FORMAT:CAPS" title="G_GINT16_FORMAT"><span class="type">G_GINT16_FORMAT</span></a>.
</p>
<p class="since">Since 2.6</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GOFFSET-MODIFIER:CAPS"></a><h3>G_GOFFSET_MODIFIER</h3>
<pre class="programlisting">#define G_GOFFSET_MODIFIER      G_GINT64_MODIFIER
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#goffset" title="goffset"><span class="type">goffset</span></a>. It is a string literal. See also
<a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-MODIFIER:CAPS" title="G_GINT64_MODIFIER"><span class="type">G_GINT64_MODIFIER</span></a>.
</p>
<p class="since">Since 2.20</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GOFFSET-FORMAT:CAPS"></a><h3>G_GOFFSET_FORMAT</h3>
<pre class="programlisting">#define G_GOFFSET_FORMAT        G_GINT64_FORMAT
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#goffset" title="goffset"><span class="type">goffset</span></a>. See also <a class="link" href="glib-Miscellaneous-Macros.html#G-GINT64-FORMAT:CAPS" title="G_GINT64_FORMAT"><span class="type">G_GINT64_FORMAT</span></a>.
</p>
Since: 2.20</div>
<hr>
<div class="refsect2">
<a name="G-GINTPTR-MODIFIER:CAPS"></a><h3>G_GINTPTR_MODIFIER</h3>
<pre class="programlisting">#define G_GINTPTR_MODIFIER      "l"
</pre>
<p>
The platform dependent length modifier for conversion specifiers for scanning
and printing values of type <a class="link" href="glib-Basic-Types.html#gintptr" title="gintptr"><span class="type">gintptr</span></a> or <a class="link" href="glib-Basic-Types.html#guintptr" title="guintptr"><span class="type">guintptr</span></a>. It is a string literal.
</p>
<p class="since">Since 2.22</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GINTPTR-FORMAT:CAPS"></a><h3>G_GINTPTR_FORMAT</h3>
<pre class="programlisting">#define G_GINTPTR_FORMAT        "li"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#gintptr" title="gintptr"><span class="type">gintptr</span></a>.
</p>
<p class="since">Since 2.22</p>
</div>
<hr>
<div class="refsect2">
<a name="G-GUINTPTR-FORMAT:CAPS"></a><h3>G_GUINTPTR_FORMAT</h3>
<pre class="programlisting">#define G_GUINTPTR_FORMAT       "lu"
</pre>
<p>
This is the platform dependent conversion specifier for scanning and
printing values of type <a class="link" href="glib-Basic-Types.html#guintptr" title="guintptr"><span class="type">guintptr</span></a>.
</p>
<p class="since">Since 2.22</p>
</div>
</div>
</div>
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